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Comte's Positive Philosophy. By G. H. Le...
Biology ) as much as may be known of Mau . la an inner centre closely , nay , inseparably connected with both , stands Chemistry , or the science of molecular action . Thu * is the circle complete . I need scarcely say that all such divisions are arbitrary . Nature admits of no distinct lines of demarcation . You earinot say , here ends the inorganic world , and here begins the organic ; you cannot say , here we see the vegetable domain cease , and here the animal commence ; but you can and do say , this rose is a plant , this lion is " an animal : Therefore , although Chemistry is inseparable from Physics , and Biology is inseparable from Chemistry , when analysis conducts us to ultimate principles , yet such distinctions are necessary and convenient .
Physics did not ( according to Comte ) begin definitely to disengage itself from Metaphysics , and to take a truly- positive character , until after the great discoveries of Galileo , on the fall of heavy bodies ; whereas Astronomy was really positive , under the purely geometrical point of view , from the foundation of the School of Alexandria . Here , therefore , we ought not only to look for the direct influence of the greatest complication in the phenomena , but also expect to find the scientific condition of Physics much less satisfactory than that of Astronomy , as well under the speculative point of view , in respect of the purity and the co-ordination of its theories , as under the practical point of view , in regard to the extent and exactness of
the predictions that result from it . In truth , the gradual formation of this science during the two last centuries , was owing to the philosophical impulse of the precepts of Bacon , and the conceptions of Des Cartes , which necessarily made its general progress much more rational , by direetly establishing the fundamental conditions of the universal positive method . But , however important this great power may have been in accelerating the natural progress of physical philosophy , the long dominion of the primitive metaphysical habits was so absolute * and the positive spirit , which
only use could develop , remained so imperfectly characterised , that this science could not in so short a time acquire complete positivism—ft state not attained by astronomy itself , as respects the mechanical part of it , before the middle of this period . Thus , starting from the point where our philosophical examination has now arrived , we find in the different fundamental sciences remaining for our consideration , more and more profound traces of the metaphysical spirit from which astronomy , of all the branches of natural philosophy , is now completely freed . This antiscientific influence wilt not be found limited to details of slight
importance . We shall find that it notably alters the fundamental conceptions of science , which , as it appears tome , has not , even in the case of physics , yet taken entirely , its definite" philosophical character . And first , as to the extent of the domain of the science of Physics . Like Chemistry , it has for its object the discovery of the general laws of the Inorganic world . The study of these laws is completely distinct from that of the Science of Life , as from that of Astronomy , which is confined to the consideration of the forms and movements of the great bodies of nature . But the distinction ( a real and indispensable one ) between Physics and Chemistry is less precisely marked , and modern discoveries " are rendering it more difficult to be made . There are , however , three general considerations which , taken together , make the division between the two
sciences quite distinct . The first consists in the characteristic connexion between the necessary generality of truly physical questions , and the speciality no less inherent in investigations purely chemical . Even the philosophers of the seventeenth century had some glimpse of this . All the conceptions of physics , properly so called , are more or less applicable to all bodies whatever ; while , on the contrary , every chemical idea necessarily relates to an action peculiar to certain substances , whatever resemblances we may otherwise find between the different cases . This fundamental contrariety between the two cate-UUV « Jl »»»* p < H ¦ w p *»» yiiwvvt ^ - ^ - « — —¦ — - ^/ j
gories of phenomena , is always distinctly marked . Weight , for example , is shown in all bodies ; so also are the phenomena of thermology , acoustics , optics , and even of electricity j there being only a simple inequality of degree in their manifestation . The compositions and decompositions of chemistry , on the other hand , show radically specific properties , varying both in the elementary and compound substances . The apparent exception to the generality of physical studies , in the case of magnetism , was dispelled by the discovery that its phenomena are only a modification of the undeniably general phenomena of electricity .
The second elementary consideration distinguishing Physics from Chemistry , is of less importance , and indeed it rests on less firm grounds than the preceding one , although susceptible of being turned to proper use . It consists in this , that the phenomena considered in physics refer to the masses , and in chemistry to the molecules j whence the habitual denomination of molecular physics , formerly given to the latter science . But purely physical phenomena are often molecular . The weight of a
mass , for example , is the total weight of all the seprirate molecules in it . Again , in chemistry , a certain mass is required to show chemical action . Still there is much truth in the distinction . In order to produce chemical phenomena , one , at least , of the bodies between which the chemical action is to take place , must be in a state of extreme division , and even , most frequently , in a state of true fluidity ; and without this , the action will not be produced : while , on the contrary , this preliminary condition is never indispensable to the production of any physical phenomenon , properly so called , but is even a circumstance always unfavourable to it , although it i » not tufficicnt constantly to prevent it .
alters their nature : and it is a modification of this sort that essentially constitutes the phenomenon . The greater number of the agents considered in physics are doubtless susceptible , when their influence is very energetic or very prolonged , of effecting , by tfaemselves , some compositions and decompositions perfectly identical with chemical action , properly sp called j and this is why there is so natural and so direct a connexion between Physics and Chemistry . But at this degree pf action , the phenomena pasjs , in fact , from the domain of the first science , and enter that of the second .
Finally , a third general remark is perhaps more suited than any other precisely to distinguish physical phenomena from chemical . In foe former ' the constitution of the bodies , that is to say , the mode of arran gement of their particles may change , although most frequently no essential alternati on of it actually takes place j but their nature , that is to say , the composition of their molecules , remains constantly unalterable . In the latter , oil the contrary , not only is there always a change of state as respects some one of the bodies -in question , but the mutual action , of these bodies necessarily
It appears to me that the ensemble of the preceding considerations suffices to give us a precise definition of the proper object of physics , when strictly circumscribed within its natural limits . We see that in this science we study ike laws which govern the general properties of bodies ordinarily viewed in their mass , and constantly placed in circumstances capable of maintaining intact the composition of their molecules , and even rftostfre * quently their state of aggregation . Besides , to act up to the true spir it of philosophy , we always require that every science worthy of the name have for its evident aim , the establishing , on sure grounds , of a corresponding
order of predictions . In order , therefore , to complete the definition , it is indispensable that we add , that the ultimate object of the theories of physics is to foresee , as epcactly as possible , all the phenomena which may be presented by a body placed in any given circumstanceSi , excluding always those which could alter its nature . It is not to be doubted that this end is rarely attained in a complete and perfectly precise manner , but this is only because the science is imperfect . Were , its actual imperfection much greater than it is , such would still be its necessary destination .
From this simple and summary exposition of the general object of physical investigations , it is easy to perceive that they necessarily present greater complexity than astronomical studies . The Jatter are limited to the two most simple andelementary-aspects of the bodies there considered , —namely , their forms and their movements . In Physics , on thecontrary the bodies are accessible to all our senses , —the general conditions which characterize their actual existence are considered , and they are studied under a great number of different and mutually Complicated relations Physics must inevitably be less perfect than astronomy ; and were it not for the extension of the means of exploration in the former , in accordance
with the law mentioned in a previous article ,-r-the increased imperfection of Physics might be conceived , & priori , as rendering a science impossible . The method of Comparison is not more applicable here than in Astronomy ; but it is otherwise with Experiment . Observation ( no longer confined to that of a single sense ) , and experiment have their most complete development in physics . In organic physics , as will afterwards be seen , it is impossible to obtain the requisite conditions of a perfect experiment . The freedom of choice of the case ( whether natural or artificial ) rapst fitted to manifest the phenomena best , constitutes the chief characteristic of the art of philosophical experiment , and this freedom is found more in Physics than in Chemistry . It is to the development of the former that the
creation of the art is due . . Next to the rational use of the Experimental Method , the application , more or less complete , of Mathematical Analysis forms the principal basis on which the perfection of Physics rests . It is here that the actual range of this Analysis in natural philosophy finds its limit ; and in the sequel of Comte ' s work it is shown how chimerical it would be to hope that its domain will be further extended , even to Chemistry , with any real efficacy . The comparative fixity and simplicity of physical phenomena ougnt naturally to permit an extensive employment of Mathematics , although it This appli
is much less adapted to physical than to astronomical studies . - cation may occur under two very different forms , the one direct , the other indirect . The first takes place when the phenomena are such as to P " " * of our immediately finding in them a fundamental numerical law , whicft becomes the basis of a more or less prolonged series of analytical ««* " ?" tions , as in the eminent example of the great Fourier when he created m * beautiful mathematical theory of the distribution of caloric , founded alt ^ gether on the principle of the thermological action between two bodies being proportional to the difference of their temperatures . Most frequently , on the contrary , mathematical analysis is introduced only indirectly , that is ,
after the phenomena have been connected with some geometrical or roecnanical law by means of a course of experiment more or lees difficult , an then , it is not to physics , properly speaking , that the analysis » s flPPu ? but to geometry or mechanics . Among other examples , we may cite w theories of reflection or of refraction , as respects geometry / and tuose weight or of part of acoustics , as respects mechanics , , The application qf mathematics to phywd » pugbt only to take p lace , w ^ with extreme circumspection too , when assurance has been obtained ot reality of the physical facts from which the mathematical deduction * . j to be made . The neglect of this rule has occasioned numerous anaiyi labours founded on extreme hypotheses or on chimerical conceptions , ft " has often converted physical tfudief itttp jmp w ^ thematfcal e * wc » w « .
420 ? Ff^ ¦ :$$^:$^& - ' . C^
420 ? ff ^ ¦ : $$ ^ : $ ^& - ' . C ^
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Citation
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Leader (1850-1860), May 29, 1852, page 20, in the Nineteenth-Century Serials Edition (2008; 2018) ncse.ac.uk/periodicals/l/issues/cld_29051852/page/20/
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